Objectives: Enhance analysis and identification of metal complexes in biological materials. Improve analytical methods with detection limits on the order of nanograms to picograms in milligram samples. Emphasize analysis of platinum, gallium, calcium and magnesium compounds as they relate to diagnosis and chemotherapy. Methods employed: Flameless atomic absorption spectrophotometry for analysis of specific elements. Chemical agents are used to promote release of elements from the biological matrix more smoothly and completely. Solvent extraction may be very useful for many applications. Electronic control of the temperature program for combustion allows materials with different combustion characteristics to be analyzed. Electrophoresis to fractionate proteins with subsequent determination of metal species among fractions. In some cases, ultrafiltration is required to concentrate proteins enough to permit detection of metals. Major findings: Sensitivity of platinum determination is approximately one nanogram. Urine and plasma samples from dogs treated with cis-dichlorodiammine platinum have been directly analyzed as a function of time. More than half of platinum administered appears in the urine within about two hours; the remainder is released in the urine much more slowly. Samples of various tissues from treated dogs have been analyzed after acid digestion. The results indicate that loss of platinum taken up in tissue is very slow. Direct analysis of gallium has given erratic results to date. Significance: Quantitation, identification and characterization of metal species at trace levels in biological tissue is important in biochemical research and environmental toxicology. Characterization of such compounds in tissues and body fluids can help identify drug action and suggest other potentially useful compounds. Methods under development offer an alternative to administering radiolabeled substances in human subjects. Proposed course: Extend applicability of direct combustion techniques to more tissue types by use of suitable time-temperature relationships; try to minimize need for pretreatment. Complete analyses required for pharmacokinetic modeling. Perform referee analyses for metals using neutron activation analysis where applicable. Improve analysis for gallium.